Folding stage construction



R. C. BUE

FOLDING STAGE CONSTRUCTION Nov. 7, 1967 3 Sh'eets-Sheet'l Filed Nov. 22, 1965 E 5 Z W m5 p o T I T D M M A H c a .i Q Am. Q Q \fi mm 1 m M. m\ m\ low \w 3 g. i 3 SN T 3 m w iv- I?iiflmmfifilmkw w I up it 1 \f k? m R L AQQ Qi m Nov. 7, 1967 R. BUE 3,351,029

FOLDING STAGE CONSTRUCTION Filed Nov. 22, 19 65 a Sheets-Sheet 2 4a h. n, m.

INVENTOR.

ATTORNEKS R. c. BUE 3,351,029

FOLDING STAGE CONSTRUCTION r 3 Sheets-Sheet 5 23 24 2 22 2423 E 0 W M R H fi 7 1 W N 1H 0 0 r n R N A .L 3.4 u A m N (J u H y W -25 W mm 0 H? M 7 Z m f 4 11 4 WW 4 5 0 6 m 7 I L 5 G W. V w G 2 G I f o 0/ E M I F fi 50 R M a a a F m m {a H UT w 6 6 fiilwl 8 \MMM 7 @l mhllhh llw /)Z). G I .!T\ 8 f r I) h I Hui 9 n F \I 5 H 5 N am? A n Z o w L w M 5 4 Nov. 7, 1967 Filed Nov. 22, 1965 United States Patent C) 3,351,029 FOLDING STAGE CONSTRUCTION Richard C. Bue, Minneapolis, Minn, assignor to Sico Incorporated, Minneapolis, Minn. Filed Nov. 22, 1965, Ser. No. 509,138 1 Claim. (Cl. 108-112) ABSTRACT OF THE DISCLOSURE Folding stage construction having a pair of top elements supported at their adjacent inner ends by supporting structure mounting the top elements for pivotal movements between horizontally and generally vertically disposed position, and at their outer ends by foldable legs. Linkage between the inner end portions of the top elements and the supporting structure mount the top elements in such manner that the inner ends are disposed in substantially abutting or contiguous relationship when horizontally disposed. Generally verticaly movable wheels, mounted on the supporting structure, are connected to the top elements by links cooperating with said linkage to raise and lower the wheels responsve to movements of the top elements between their horizontal and generally vertical positions.

Summary of the invention This invention is in the nature of an improvement on portable or folding stages of the type disclosed in US. Letters Patent No. 2,987,754, issued to Kermit H. Wilson. The primaryobject of this invention is the provision of a folding stage including a pair of flat top elements which are movable between horizontally disposed operative positions and upwardly folded generally parallel storage positions, "and in which, in their operative positions, have their adjacent inner ends disposed in substantially abutting or contiguous relationship at a common level, wherebyto eliminate any upwardly projecting elements over which the occupant of the stage may trip or stumble, and to elminate a bridging member between the top sections as disclosed in the Wilson patent, above-identified. \To this end I provide linkage underlying the inner end portions of the top elements providing pivotal connections therefore below the level of the top elements, wherein the axes of the pivotal connections are movable generally toward and away from each other during movements of the top element. This invention further contemplates a wheel-equipped member mounted on the supporting structure for generally vertical movements, rigid links cooperating with the linkage mounting the top elements for raising and lowering the wheel-carrying members responsive to movements of the top elements between their operative and storage positions, supporting legs at the outer end portions of the top elements, and control arms connected to the legs and to said supporting structure for moving the legs between operative supporting positions ggenerally normal to the top elements and folding positions generally parallel to the top elements responsive to said rnovement of the top elements.

Referring to the drawings, which illustrate the invention, and in which like reference characters indicate like parts throughout the several views:

-FIG. 1 is a view in side elevation of a folding or portable stage produced in accordance with this invention,

some parts being broken away;

FIG. 2 is a fragmentary view corresponding to a portion of FIG. 1, some parts being broken away and some parts being shown in section;

FIG. 3 is a view in side elevation of the stage of FIG.

'1 but showing the stage in a folded condition;

3,351,029 Patented Nov. 7, 1967 FIG. 4 is a view in end elevation of the stage in a folded condition;

FIG. 5 is an enlarged fragmentary view partly in end elevation and partly in section, taken on the line 5-5 of FIG. 1;

FIG. 6 is an enlarged view corresponding to a portion of FIG. 2, some parts being broken away and some parts being shown in section;

FIG. 7 is a fragmentary view in side elevation showing a modified arrangement; and

FIG. 8 is a fragmentary transverse section taken substantially on the line 8-8 of FIG. 7.

In the preferred embodiment of the invention illustrated in FIGS. 1-6, a foldable and] portable stage is shown as involving a pair of cooperating flat top elements or sections 1 and 2 that are preferably rectangular and which may be made from any suitable material, such as plywood, wood planks, particle board or the like. The top elements 1 and 2 are bolted or otherwise regidly secured to generally rectangular frames 3 and 4 respectively, the frames 3 and 4 preferably being made from structural angle iron or the like, and each comprising laterally spaced side frame rails 5 at opposite longitudinal edge portions of the top elements 1 and 2, cross rails 6 and 7, and an intermediate longitudinal rail 8. The several rails 58 are welded or otherwise rigidly secured together to provide a rigid frame structure, the cross rails 6 being disposed along the outer edge portions of their respective top elements 1 and 2, the cross rails 7 being disposed in spaced relation to the inner ends of their respective top elements 1 and 2.

The top elements 1 and 2 are supported at their adjacent inner end portions by a supporting structure indicated generally by the reference numeral 9. The supporting structure 9 comprises a pair of laterally spaced vertically disposed legs 10 which normally underlie the inner end portion of the top element 1, and a like pair of vertically disposed legs 11 which normally underlie the inner end portion of the top. element 2. Each leg 10 is rigidly connected to an opposite leg 11 by upper and lower cross member 12 and 13 respectively and connected to the legs 10 and 11 by welding or the like. The legs 10 and 11 are rigidly held in spaced apart relationship transversely of the stage by diagonally disposed brace members 14 bolted or riveted at their opposite ends to the legs 10 and 11, see particularly, FIGS. 1, 3 and 4. The outer ends of the top elements 1 and 2 are supported from the ground or floor by respective leg structures each comprising a pair of laterally spaced legs 15 and 16 respectively. The legs 15 are pivotally secured at their upper ends, as indicated at 17, to brackets or the like 18 welded or otherwise rigidly secured to the end rail 6 at the outer end of the top section 1, on aligned horizontal axes extending transversely of the top element 1. In like manner, the legs 16 are pivotally secured, as indicated at 17, to brackets 18 secured to the end rail 6 of the top element 2, the legs 15 and 16 being movable between operative position generally normal to their respective top elements 1 and 2, as shown in FIG. 1, and inoperative folded positions generally parallel to their respective top elements 1 and 2 as shown in FIG. 3. At their lower ends, the legs 15 and 16, as well as the legs 10 and 11, are provided with floor engaging cushions or feet 19. As shown particularly in FIGS. 2 and 6, the upper ends of the legs 10 and 11 engage the bottom surfaces of the top elements 1 and 2 respectively to aid in supporting their respective top elements 1 and 2 in their generally horizontally disposed operative positions.

As shown in FIGS. 1, 2 and 6-, when the top elements are disposed in their generally horizontal operative positions, the inner ends 1a and 2a thereof respectively, are

disposed in substantially abutting relationship; and, with reference to FIG. 5, it will be noted that the cross members 12 between each leg and its opposite leg 11 are arranged in laterally spaced pairs, preferably made from metallic bar stock. The supporting structure 9 further includes two pairs of rigid primary links 20 and two pairs of generally L-shaped secondary links 21, a pair of each thereof underlying the inner end portion of a different one of the top elements 1 and 2. At their upper ends, the primary and secondary links are pivotally secured to bifurcated brackets 22 by means of pivot bolts or the like 23 and 24 respectively, the brackets 22 being welded or otherwise rigidly secured to respective ones of the cross rails 7 and extending toward the inner ends 1a and 2a of their respective top elements 1 and 2. The pivot bolts 23 and 24 are disposed on parallel horizontal axes which extend in directions parallel to the inner ends 1a and 2a of their respective top elements 1 and 2. The lower ends of the primary and secondary links 20 and 21 are pivotally connected to adjacent cross members 12 by means of respective pivot bolts 25 and 26 disposed on axes parallel to the axes of the pivot bolts 23 and 24. With reference to FIG. 5, it will be seen that the secondary links 21 are disposed within their respective bifurcated brackets 22 and between adjacent ones of the cross members 12, the primary links 20 being disposed laterally outwardly of adjacent ones of the brackets 22 and the adjacent pair of the cross members 12. It will be further noted, particularly with reference to FIG. 6, that the axes of the several pivot bolts 23 and 24 are disposed in a common horizontal plane substantially below the level of the top surfaces of the top elements 1 and 2 when the top elements 1 and 2 are disposed in their horizontal operative positions; and that the axes of the several pivot bolts 25 and 26 of cooperating links 20 and 21 are spaced apart a greater distance than that between the axes of cooperating pivot bolts 23 and 24.

The above-described mounting means for the top elements 1 and 2 permits the top element to be swung or pivotally moved between their generally horizontal operative positions shown in FIG. 1 and by full lines in FIGS. 2 and 6, and inoperative folded positions shown in FIGS. 3 and 4. During said swinging movement of either of the top elements 1 or 2, their respective primary and secondary links 20 and 21 swing in paths wherein the axes of their respective pivot bolts 23 and 24 travel in arcs shown by broken lines 27 and 28 respectively. Each top element 1 and 2 pivots on the axis of its respective pivot bolts 23, this axis being moved along the path of the are 27 by the action of its respective secondary link 21. During initial swinging movements of either top element 1 or 2 from its horizontal position, the axis of its pivot bolts 23 is moved almost directly away from the other top element or in a direction toward the outer end of its respective top element. During this initial movement, the top corner edge of the inner end 1a or 2a moves directly away from the adjacent inner edge of the opposite top element and, as the top element is swung upwardly toward its inoperative folded position, the inner end 1a or 2a thereof travels in a generally S-shaped path, indicated by a broken line 29 in FIG. 6. Obviously, when the top elements 1 and 2 are swung downwardly from their folded positions to their operative positions, the inner ends 1a and 2a thereof retrace the paths indicated by the broken lines 29. With this arrangement, it is possible to dispose the pivot axes of the top elements 1 and 2 below the level thereof, and yet have the inner ends 1a and 2a thereof in substantially abutting relationship or in full abutting relationship, if desired, without one of the ends 1a or 2a interfering with the other thereof during swinging movements of the top elements 1 and 2 between their operative and inoperative positions.

For the purpose of bracing the outer leg structures comprising the several legs and 16, and for moving the same between their operative positions generally normal to their respective top elements 1 and 2, as shown in FIG.

1, and their inoperative folded positions shown in FIGS. 3 and 4, I provide pairs of rigid control arms 30' and 31. The control arms 30 are pivotally connected at their inner ends each to a different one of the legs 10, as indicated at 32, and at their outer ends to a respective one of the legs 15, as indicated at 33, the pivot axes of the pivotal connections 32 and 33 being parallel to the pivotal connections of the various primary and secondary links 20 and 21 respectively. In like manner, the control arms 31 are pivotally connected at their inner ends each to a different one of the legs 11, as indicated at 34, and at their outer ends each to an adjacent one of the legs 16, as indicated at 35.

For the purpose of rendering the folding stage easily movable from place to place in its folded condition, I provide a pair of transverse members 36 and 37 each having a pair of vertically disposed tubular elements 38 at its opposite ends, the tubular elements 38 of the transverse member 36 slidably encompassing the legs 10 and the tubular elements 38 of the transverse member 37 slidably encompassing the legs 11, both of the transverse members 36 and 37 being disposed below the cross members 13 of the supporting structure 9. Each of the transverse members 36 and 37 is provided with a pair of spaced caster wheels or the like 39 intermediate the tubular elements 38, see FIGS. 1, 3 and 4. Each of the top elements 1 and 2 is provided with a pair of laterally spaced bifurcated brackets 40 and 41 that are welded or otherwise rigidly secured to the inner cross rails 7 of their respective top elements 1 and 2. A pair of rigid support links 42 are pivotally connected at their upper ends to the brackets 40 and at their lower ends to spaced portions of the transverse member 36, as indicated at 43 and 44 respectively; and a like pair of support links 45 are pivotally secured at their upper ends to the brackets 41 and at their lower ends to the transverse member 37, as indicated at 46 and 47 respectively, the axes of the pivotal connections 43, 44, 46 and 47 being parallel to the axes of the various pivotal connections of the primary and secondary links 20 and 21.

As each top element 1 or 2 is raised from its operative position of FIGS. 1 and 2 toward its folded inoperative position of FIG. 3, the brackets 40 and 41 swing downwardly about the axes of the primary link pivot connections 23 to impart downward movement to the support links 42 and 45 and their respective transverse members 36 and 37 until the caster wheels 39 engage the floor or ground. Further upward swinging movements of the top sections or elements 1 and 2 imparts a lifting movement to the primary links 20 to raise the legs 10 and 11 out of engagement with the floor or ground, as shown in FIG. 3, whereby the folded table or stage may be easily moved to another location for further use or storage. Preferably, the top element 2 is provided at its outer end with a hook 48 that is pivotally secured to the cross rail 6 thereof, whereby the same may be hooked over the adjacent outer ends of the top elements 1 and 2 in their folded positions to prevent accidental unfolding of the top elements 1 and 2.

In the modified arrangement illustrated in FIGS. 7 and 8, a supporting structure is shown as comprising a pair of laterally spaced support brackets 49 and 50 that are adapted to be bolted or otherwise rigidly secured to a building wall or the like, indicated at 51. Each bracket 49 and 50 is provided with an upstanding leg portion 52 that is adapted to engage the lower surface of a top element 53 substantially identical to the top element 2. The inner end 53a of the top element 53 is adapted to substantially abut the adjacent surface of the wall 51, the outer end of the top element 53 being sup ported by outer legs 54, one of which is shown, the legs 54 being substantially identical to the legs 16. The legs 54 are pivotally connected at their upper ends to the outer end portion of the top element 53, swinging movement thereof being controlled by a pair of rigid control arms 55 secured at their opposite ends to the brackets 49 and legs 54, as indicated at 56 and 57 respectively. The top element 53 is provided at its inner end portion with primary and secondary links 58 and 59 that are identical to the links 20 and 29 respectively, and which operate in the same manner as the links 20 and 21 to mount the inner end of the top element 53 for swinging movements between its operative horizontal position, shown in FIG. 7, and a generally vertical disposed folded position, not shown, but in closely spaced generally parallel relation to the surface of the wall 51. During swinging movements of the top element 53, between its opeartive and folded positions, the inner end 53a partakes of movements substantially identical to those indicated by the broken lines 29 in FIG. 6. Thus, when the top element 53 is moved to its operative position shown, the inner end 53 thereof is sufficiently close to the surface of the wall 51 to prevent heels, chair legs or other objects from being caught between the inner end 53a and the wall 51.

It will be appreciated that, while I have described the aforementioned structure as being a folding and portable stage, folding tables or leg structures are equally well adapted to this construction. Hence, while the present claims define the structure as a folding stage, it is desired that the same apply to folding tables as well.

This invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the objectives set forth; and, while I have shown and described a preferred embodiment of folding stage, platform or table, and a modified form thereof, it will be understood that the same is capable of further modification without departure from the spirit and scope of the invention, as defined in the claim.

What is claimed is:

A folding stage comprising:

(a) a top including a pair of normally horizontally disposed flat top elements having substantially abutting inner ends and having a pair of reinforcing frames one each underlying a different one of said top elements and secured thereto,

(b) a supporting structure including a pair of spaced inner leg structures each underlying a different one of said top elements adjacent their inner ends in the horizontal positions of said top elements and each having lower ground-engaging ends, and a generally horizontal cross member connecting said leg structure,

(c) support means for the outer ends of said top elements, and

(d) means mounting said top elements adjacent their inner ends on said supporting structure for independent swinging movement between their normal generally horizontal operative positions overlying said supporting structure and a generally vertical folded position, said means comprising:

(1) a pair of primary straight links each pivotally secured to said cross member below the inner end portion of a different one of said top elements on an axis parallel to the inner ends of said top elements,

(2) a pair of secondary angular links pivotally secured to said cross member on closely adjacent axes under the ends of the respective top elements and each in horizontally spaced parallel relation to the axis of the pivotal connection of an adjacent one of said primary links to said cross member,

(3) and primary and secondary pivot means pivotally securing said primary and secondary links respecitvely each to the frame structure of a respective one of said top elements below the top thereof and on axes parallel to the axes of the pivotal connection of said links to said cross member and spaced closer than the spacing of their axes on the cross member,

(4) said primary pivot means defining the axes of said swinging movement of their respective top elements,

(5) said primary and secondary links and the pivotal connections thereof to the top element frames and said cross member being so arranged that, during upward swinging movement of either top element away from said operative position thereof the respective secondary link imparts movement to its top element to move its cooperating primary pivot means initially in a direction toward the outer end of said top element, whereby the inner end of its respective top element at the top thereof moves away from the inner end of the other top element in an outward and downward generally S- shaped path.

References Cited UNITED STATES PATENTS 5/ 1927 Bayer 5142 4/1961 Wilson 108-112 8/1962 Schlegel 108112 FRANCIS K. ZUGEL, Primary Examiner. 

